Prior to God's narrowing his church down to a single family and nation--and actually we can probably take this up to the time of the entrance to Canaan--there were God's spokesmen (prophets) everywhere there was true faith. Examples: Melchizedek, Elihu, and even Balaam who (though he prostituted his gift) truly prophesied.
After the days of Moses, however, there are no true prophets (that I know of) outside of Israel. Indeed, unto them alone, where the church resided, God had entrusted his Word, first spoken and then recorded.
In the post-Israelite world, the international church is the "trustee" of the Bible.